On Fri, Aug 02, 2019 at 05:00:45PM -0500, Goldwyn Rodrigues wrote:
> From: Goldwyn Rodrigues <rgoldwyn@xxxxxxxx>
>
> This helps filesystems to perform tasks on the bio while
> submitting for I/O. Since btrfs requires the position
> we are working on, pass pos to iomap_dio_submit_bio()
What /does/ btrfs_submit_direct do, anyway? Looks like it's a custom
submission function that ... does something related to setting
checksums? And, uh, RAID?
> The correct place for submit_io() is not page_ops. Would it
> better to rename the structure to something like iomap_io_ops
> or put it directly under struct iomap?
Seeing as the ->iomap_begin handler knows if the requested op is a
buffered write or a direct write, what if we just declare a union of
ops?
e.g.
struct iomap_page_ops;
struct iomap_directio_ops;
struct iomap {
<usual stuff>
union {
const struct iomap_page_ops *page_ops;
const struct iomap_directio_ops *directio_ops;
};
};
--D
> Signed-off-by: Goldwyn Rodrigues <rgoldwyn@xxxxxxxx>
> ---
> fs/iomap/direct-io.c | 16 +++++++++++-----
> include/linux/iomap.h | 1 +
> 2 files changed, 12 insertions(+), 5 deletions(-)
>
> diff --git a/fs/iomap/direct-io.c b/fs/iomap/direct-io.c
> index 5279029c7a3c..a802e66bf11f 100644
> --- a/fs/iomap/direct-io.c
> +++ b/fs/iomap/direct-io.c
> @@ -59,7 +59,7 @@ int iomap_dio_iopoll(struct kiocb *kiocb, bool spin)
> EXPORT_SYMBOL_GPL(iomap_dio_iopoll);
>
> static void iomap_dio_submit_bio(struct iomap_dio *dio, struct iomap *iomap,
> - struct bio *bio)
> + struct bio *bio, loff_t pos)
> {
> atomic_inc(&dio->ref);
>
> @@ -67,7 +67,13 @@ static void iomap_dio_submit_bio(struct iomap_dio *dio, struct iomap *iomap,
> bio_set_polled(bio, dio->iocb);
>
> dio->submit.last_queue = bdev_get_queue(iomap->bdev);
> - dio->submit.cookie = submit_bio(bio);
> + if (iomap->page_ops && iomap->page_ops->submit_io) {
> + iomap->page_ops->submit_io(bio, file_inode(dio->iocb->ki_filp),
> + pos);
> + dio->submit.cookie = BLK_QC_T_NONE;
> + } else {
> + dio->submit.cookie = submit_bio(bio);
> + }
> }
>
> static ssize_t iomap_dio_complete(struct iomap_dio *dio)
> @@ -195,7 +201,7 @@ iomap_dio_zero(struct iomap_dio *dio, struct iomap *iomap, loff_t pos,
> get_page(page);
> __bio_add_page(bio, page, len, 0);
> bio_set_op_attrs(bio, REQ_OP_WRITE, flags);
> - iomap_dio_submit_bio(dio, iomap, bio);
> + iomap_dio_submit_bio(dio, iomap, bio, pos);
> }
>
> static loff_t
> @@ -301,11 +307,11 @@ iomap_dio_bio_actor(struct inode *inode, loff_t pos, loff_t length,
> iov_iter_advance(dio->submit.iter, n);
>
> dio->size += n;
> - pos += n;
> copied += n;
>
> nr_pages = iov_iter_npages(&iter, BIO_MAX_PAGES);
> - iomap_dio_submit_bio(dio, iomap, bio);
> + iomap_dio_submit_bio(dio, iomap, bio, pos);
> + pos += n;
> } while (nr_pages);
>
> /*
> diff --git a/include/linux/iomap.h b/include/linux/iomap.h
> index 5b2055e8ca8a..6617e4b6fb6d 100644
> --- a/include/linux/iomap.h
> +++ b/include/linux/iomap.h
> @@ -92,6 +92,7 @@ struct iomap_page_ops {
> struct iomap *iomap);
> void (*page_done)(struct inode *inode, loff_t pos, unsigned copied,
> struct page *page, struct iomap *iomap);
> + dio_submit_t *submit_io;
> };
>
> /*
> --
> 2.16.4
>
